Yohan Blake made a huge signal of intent with a shock win over Usain Bolt in the 100 metres at the Jamaican Olympic trials.

Olympic champion Bolt and world champion Blake locked horns less than a month before London 2012 and the race lived up to the hype as Blake clocked a personal best of 9.75 seconds, which is also the fastest time in the world this year.

Bolt was slower out of the blocks than Blake and had to settle for second in 9.86 followed by former world record holder Asafa Powell in 9.88. All three qualified for the Olympics.

"I thought it was a good race but everybody kept moving in the blocks and that kind of threw me off," Bolt said. "I think overall I executed through the first 60 metres but the last part not so good, overall it was okay. For me it is just one of those things."

Glen Mills, who coaches both Blake and Bolt, told Reuters: "We are right where we want to be going into London. We just want to keep them healthy. The strategy, we didn't send him (Blake) to Europe and he is in far better shape than Bolt at this time.

"We have four weeks (until the Olympics) and we will take it in stride. We know what to do, so we'll get there.

"Bolt is a tough cookie and I think he will survive."

Bolt and Blake will return to the track on Saturday where they will be looking to book their tickets to London in the 200m.

Shelly-Ann Fraser-Pryce wowed the crowd in Kingston with a time of 10.70s in the 100m, the seventh fastest run of all time.